TDC-DCO Resolution Matching for PVT-Stable Frequency Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional adaptive frequency control methods in digital circuits face accuracy issues due to variations in Process Voltage Temperature (PVT) conditions, leading to mismatches in measurement time resolution of Time-to-Digital Converters (TDC) and cycle modulation time resolution of Digitally Controlled Oscillators (DCO), which affect the accuracy of clock frequency adjustments.
Innovation Solution
An information processing device with a voltage variation detection unit, an oscillator, a frequency divider, an adder, and a control unit that matches the measurement time resolution of the TDC with the cycle modulation time resolution of the oscillator, allowing for precise adjustments to maintain accurate adaptive frequency control across varying PVT conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If adaptive frequency control is implemented using TDC and DCO, then timing error is avoided, but measurement time resolution of TDC and cycle modulation time resolution of DCO mismatch under varying PVT conditions
Solution Approach 1:
The patent changes the parameter of time resolution by dynamically adjusting the measurement time resolution of the TDC based on the cycle modulation time resolution of the DCO. This is achieved by modifying the measurement range or granularity of the TDC to match the DCO's resolution characteristics under different PVT conditions, ensuring both components operate at compatible precision levels.
Solution Approach 2:
The patent implements a feedback mechanism where the measurement time resolution of the TDC is adjusted according to the cycle modulation time resolution of the DCO. The system continuously monitors the DCO's resolution and modifies the TDC's measurement parameters accordingly, creating a closed-loop control that maintains time resolution matching despite PVT variations.
2Adaptability or versatility
If conventional adaptive frequency control is used, then clock frequency adjustment is achieved, but accuracy decreases due to PVT condition variations
Solution Approach 1:
The patent dynamically adjusts the measurement time resolution parameter of the TDC to match the DCO's cycle modulation time resolution under different PVT conditions. This parameter adaptation ensures that the frequency control accuracy is maintained across varying process, voltage, and temperature conditions by preventing resolution mismatches between the measurement and modulation components.
3Measurement precision
If TDC measurement time resolution is optimized for reference condition, then accuracy is achieved at reference PVT, but mismatch occurs under varying PVT conditions
Solution Approach 1:
The patent transforms the static measurement time resolution of the TDC into a dynamic parameter that can adapt to different PVT conditions. Instead of being fixed for reference conditions, the measurement time resolution is made variable and is continuously adjusted to match the DCO's cycle modulation time resolution, enabling the system to maintain accuracy across varying process, voltage, and temperature conditions.
Solution Approach 2:
The patent changes the measurement time resolution parameter of the TDC based on the operating PVT conditions. By monitoring the DCO's cycle modulation time resolution under different conditions and adjusting the TDC's measurement parameters accordingly, the system maintains optimal measurement precision across the full range of PVT variations rather than being optimized only for reference conditions.
Data Source
AI summary
A TDC measures a time difference between delay time that is in accordance with voltage variations. A DCO 155 generates an oscillation signal having a cycle that is in accordance with an input signal. A frequency divider 156 generates a divided signal by dividing the oscillation signal. An adder 154 inputs, to the DCO 155, a signal obtained by adding a second signal that changes an oscillation cycle of the DCO 155 in accordance with the time difference measured by the TDC to a first signal that is in accordance with a phase difference between the divided signal and a reference signal. A control circuit 11 obtains a measurement time resolution of the TDC and matches a cycle modulation time resolution of the DCO 155 with the measurement time resolution of the TDC.